Amid internet reports claiming the LAPD is investigating Michael Jackson’s long-time dermatologist Arnold Klein, RadarOnline.com has learned exclusively that the King of Pop was visiting Klein several times a month in the weeks leading up to his death. He was also at Klein’s office a week before he died.

“I saw him go into the men’s the bathroom after his visit about a week before he died,” one source told RadarOnline.com. “He had one of his masks on and one of his bodyguards was waiting for him to whisk him away.”

“Michael would come in three to four times a month to be treated by Dr. Klein,” another source said. “The last time I saw him, he said he wasn’t feeling well and he was having problems with his chest.”

As RadarOnline.com reported exclusively on Friday, Jackson was extremely underweight and breathing heavily on his last visit to the Klein’s office.

“He looked so slim when I saw him and he was having trouble breathing,” the source added.

All attempts to reach Arnold Klein were ignored. His office is currently locked.